General bacterial porin family. General bacterial porins are a family of proteins from the outer membranes of Gram-negative bacteria. The porins act as molecular filters for hydrophilic compounds. They are responsible for the 'molecular sieve' properties of the outer membrane. Porins form large water-filled channels which allow the diffusion of hydrophilic molecules into the periplasmic space. Some porins form general diffusion channels that allow any solute up to a certain size to cross the membrane, while other porins are sp
Cystic fibrosis transmembrane conductance regulator (CFTR) is a membrane protein and chloride channel in vertebrates that is encoded by the CFTR gene. CFTR is an ABC transporter-class ion channel that codes for a protein that conducts chloride and thiocyanate ions across epithelial cell membranes.
Understanding What Causes Cystic Fibrosis. The cause of cystic fibrosis (CF) is a defect in a gene called the cystic fibrosis transmembrane conductance regulator (CFTR) gene. This gene makes a protein that controls the movement of salt and water in and out of the cells in your body.he cause of cystic fibrosis (CF) is a defect in a gene called the cystic fibrosis transmembrane conductance regulator (CFTR) gene.